#include "stm32f10x.h"
void Delay_us(uint32_t us)
{
	SysTick->LOAD=72*us;
	
	SysTick->VAL=0x00;
	SysTick->CTRL=0x00000005;
	while(!(SysTick->CTRL&0x00010000));
	SysTick->CTRL=0x00000004;
}
void Delay_ms(uint32_t xms)
{
	while(xms--)
	{
		Delay_us(1000);
	}
}